Create LineLayout api

Source/core/layout/api/LineLayoutBlockFlow.cpp

Index: Source/core/layout/api/LineLayoutBlockFlow.cpp
diff --git a/Source/core/layout/api/LineLayoutBlockFlow.cpp b/Source/core/layout/api/LineLayoutBlockFlow.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..3288848d7376e5783817e66e7cdc486f8f5ff300
--- /dev/null
+++ b/Source/core/layout/api/LineLayoutBlockFlow.cpp
@@ -0,0 +1,21 @@
+// Copyright 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "config.h"
+#include "core/layout/api/LineLayoutBlockFlow.h"
+
+namespace blink {
+
+LineLayoutBlockFlow::LineLayoutBlockFlow(LayoutBlockFlow* blockFlow)
+    : LineLayoutBox(blockFlow)
+{
+}
+
+LineLayoutBlockFlow::LineLayoutBlockFlow(const LineLayoutItem& item)
+    : LineLayoutBox(item)
+{
+    ASSERT(!item.layoutObject() || item.layoutObject()->isLayoutBlockFlow());
+}
+
+} // namespace blink